The 1965 MGM vault fire was a major fire that erupted in Vault #7 at Metro-Goldwyn-Mayer's studio in Culver City, California, resulting in the loss of many silent and some early sound films of which no copies now exist.
1965 MGM vault fire Wikipedia
An electrical fire ignited the nitrate film stored in the vault and destroyed hundreds of silent films, including The Black Butterfly, The Divorcee, A Blind Bargain, The Big City, The Divine Woman, London After Midnight and The Actress.
Among the losses were rare examples of two-color Technicolor, including an original print of the pioneering 1922 Technicolor feature The Toll of the Sea (later incompletely restored from surviving reels of the negative) and the part-Technicolor silent So This Is Marriage?; Technicolor sequences from the early musicals The Broadway Melody and Chasing Rainbows; what was long believed to be the only surviving Technicolor print of The Mysterious Island (another copy was found in Prague in 2013); and the last known print of the all-Technicolor musical-drama The Rogue Song, which included comedy relief bits by Laurel and Hardy (only fragments from other prints and the trailer have definitely survived).
The uncut version of the Laurel and Hardy short Blotto and the silent Our Gang shorts from 1927–1929 were also destroyed in the fire. The early Three Stooges musical short Hello Pop! was widely believed to have been among the casualties, but has turned up in a private collection in Australia, with Warner Bros. (the current rights holder) in the process of restoring the film for a public release, as of 2013.
Also lost were many of the original-release prints of pre-1951 MGM cartoons, most notably the Tom and Jerry series and Tex Avery shorts, leaving only the backup prints (usually the altered reissue prints).
The inferno also destroyed pre-1924 films made by MGM's predecessors Metro Pictures, Goldwyn Pictures and Louis B. Mayer Pictures.